The main function of the reservoir in the oxygen mask is to ensure a continuous supply of oxygen to the patient, even during inhalation. It acts as a reservoir or storage for oxygen, allowing the patient to receive a higher concentration of oxygen with each breath.
The reservoir bag is typically made of a flexible material that can expand and contract. When the patient inhales, the bag fills with oxygen from the oxygen source. This ensures that the patient receives a higher concentration of oxygen, as the bag contains a larger volume of oxygen compared to just the oxygen flow rate.During exhalation, the reservoir bag deflates, but the oxygen supply is not interrupted. This is because the reservoir bag is designed to hold more oxygen than the patient can exhale, ensuring a continuous supply of oxygen during the entire breathing cycle.